Question

(A) What are some reasonable scientific options to increase the amount of Cu2+ being removed from aqueous solution by a super absorbent polymer like sodium polyacrylate? (B) Would you consider sodium polyacrylate a good tool for remediation of sites contaminated with metal salts? Why or why not? (C) Explain the mechanism behind releasing metal ions with excess HCl

Answer 1

A.( PANa) sodium polyacrylate has a swell ratio Qeq which depends on several parameters like the presence of metal (eg. Copper Cu2+), the change ion-cons, the temperature,the pH of medium.

In the presence of distilled water only the polymer is capable of retaining its macromolecular chains between more than 300 times it's weight in water. This value decreases with less acid pH (Qeq= 229 at pH=7) and with the increasing temperature ( Qeq= 313 at T = 70°C).

SUPER EFFECTIVE REMOVAL OF TOXIC METALS :

By,

1.Preparing polyacrylonitrile - grafted Arabic gum

2.Modification of the graft product with hydrazine hydrochloride.

3.Introduction of carboxyl and amide groups to the graft product.

B. Yes, it is a good tool for remediation of sites contaminated with metal salts since it is eco friendly and cost effective.

C.The adsorption kinetics followed the mechanism of pseudo- second order equation ,this indicates chemical sorption to be rate limiting step of the adsorption mechanism.